Those double bottom sections have about 20 tons of basic steel in them per frame (3 feet, .92 meters). The forward section is about 12 frames (36ft X 92ft, 33m X 85m) but there irregularities on the exact length of the torn shell plating at the ends and sides. That puts the weight at about 240 tons plus any pipes, tanks, boiler mounts, or other fittings that we can't see. Call it 250 tons.

The aft section is about 10 frames long (~6ftft, 2m) shorter, but has additional bracing for the engines and probably has the forward engine mounts, some pumps and other engine plumbing still attached so it's weight may be roughly the the same or a little more.

The Ken Marschall drawings I have are rather poor quality. They show the break at frame 25 aft and that's where the greatest compression failure evidence is seen. That's why I think Titanic broke bottom-up.

Actually this question was addressed to you mainly, since I was certain that you know the answer and you have this specific information! Now I thank you from _the_bottom_ of my heart for providing these essential data so kindly and openly!!It's of a great importance for me, really! It gives a remarkable sense of scale and the understanding of the significance of these findings!

I even see the traces of antifouling carmine paint…

Pity that these double-bottom sections can not be raised like “The Big Piece” (due to such their size & weight)…

Special Spasibo for the Ken Marschall ‘s coolest drawing diagram, I’ve never seen this before (even in such a quality)! Of course, it’s hella interesting to examine the area of the compression failure in all the details… as the strongest evidence for your famous “Bottom-up” theory! Btw, I write about it (in a measure of my understanding) in my forthcoming book to give Russian readers some education on this… 8)